Non-immunoglobulin fraction of human milk protects rabbits against enterotoxin-induced intestinal fluid secretion

Human milk was fractionated by ammonium sulphate precipitation and column chromatography. A milk fraction depleted of secretory immunoglobulin A and with an apparent molecular weight of greater than 400,000 inhibited fluid secretion induced by cholera toxin and Escherichia coli heat-labile toxin in rabbit ileal loops.